<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>03_BOM操作</title>
</head>
<body>
    <button onclick="alert('警告框')">弹出警告框</button>
    <button onclick="confirm('确认框')">您确认要删除吗</button>
    <button onclick="prompt('请输入会员卡号')">弹出输入框</button>
    <script>
        //将参数转为整数
        console.log(parseInt(6.6));//6
        console.log(parseInt(6.1));//6
        console.log(parseInt(6));//6
        console.log(parseInt('hhh'))//NaN
        console.log(parseInt('12hh'))//12

        console.log(parseFloat(5.6));//5.6
        console.log(parseFloat(5));//5
        console.log(parseFloat('hhh'));//NaN
        console.log(parseFloat('3.4hhh3.3h3.1'));//3.4
        //判断参数是否为非数字，数字得到false，非数字得到true
        console.log(isNaN('hhh')); //true
        console.log(isNaN(7)); //false
        console.log(isNaN(7.7)); //false
    </script>
</body>
</html>